One of the central tasks for controlling internal combustion engines is the determination of the crankshaft angle. Known design approaches use incremental sensors on the crankshaft and the camshaft. Ones commonly used are signal-generating disks having incremental markers in the form of the alternating positioning of teeth and tooth interstices on the signal-generating disk which in the cooperation of the signals from crankshaft and camshaft make possible a determination of the engine position with respect to an identified null position of the crankshaft (null marking). On known signal-generating disks, a marking gap is assigned to this null position which, as a rule, takes the form of an enlarged tooth clearance between two teeth, but is also able to have the form of an enlarged tooth. In response to the rotation of the crankshaft, and, with that, the signal-generating disk, the teeth are led past the sensors, whereby electrical signals are triggered in the sensors which are used to determine the crankshaft angle, and ultimately for the control and regulation of the internal combustion engine. Since no signal changes are able to be output by the sensors in response to the leading past of the marking gap, and since, however, the control and regulation of the internal combustion engine requires signal changes also for the angular section of the marking gap, it is known that one may approximate simulated sensor signal patterns from the signal pattern of the teeth and the tooth interstices that follow the marking gap.
Taking into account simulated sensor signal patterns in the control and regulation of an internal combustion engine is known, for example, from German Published Patent Application No. 43 13 331. In the method described there, a signal-generating disk in the form of a rotating part of two sensors is recorded, after detection of the improper occurrence of sensor signals in the form of angle mark signals, an operation under emergency conditions being started, in which first and second values are computed for the simulation of angle mark signals from the sequence in time of the signals of the second sensor.
The functions of the control and regulation of internal combustion engine require the signals generated by the sensors, as a rule, immediately after their generation. This applies especially to the position of the crankshaft, which represents an essential variable for the control and regulation of the internal combustion engine. However, since no signal changes are generated in response to the leading past of the marking gap, one can only fall back on the simulated sensor signal patterns described above. However, the teeth following the marking gap are generated time-wise only after the leading of the marking gap past the sensor being used, and are therefore not available for the duration of the leading past. This is a disadvantage particularly for the functions described above, which require the signals directly after their generation, with respect to optimum control and regulation. Therefore, it is the object of the present invention to state a method, using which a simulated sensor signal pattern can be made available even for the duration of the leading of the marking gap past the sensor.